The present invention is generally directed to a vehicle safety system, such as an occupant protection system, that has a central control unit and a plurality of remote devices. The present invention is particularly directed to a system with features that can minimize potential communication interruptions.
One type of vehicle safety system is an occupant protection system. The protection system includes one or more sensor devices for sensing vehicle characteristics and/or occupant characteristics. The sensed characteristics are used to determine whether a vehicle occupant needs to be protected (e.g., restrained) and/or determine a deployment profile of a device that accomplishes a protection function. Examples of the sensor devices include a vehicle acceleration sensor, an occupant position sensor, and an occupant weight sensor.
The system includes one or more actuatable protection devices for protecting (e.g., restraining) the occupant. Examples of such protection devices include an air bag module, a knee bolster module, and a seat belt pretensioner module.
As the sophistication of occupant protection systems has increased, the number and complexity of the sensor and protection devices in a single vehicle has increased. In response to the increased number and complexity of devices, there has been a movement toward centralized control of the devices to reduce cost and to increase reliability of the overall protection system. In order to accomplish the centralized control, a bus architecture is used for conveyance of communication signals. A potential exists that bus communication may be interrupted by such occurrences as crushing during a vehicle collision and associated deployment actuation of the protection devices within the system during the collision.
In accordance with one aspect, the present invention provides a distributed vehicle safety system.
The system includes a plurality of devices, each for performing a function associated with safety at a vehicle. Bus means conveys communication regarding the devices. Means electronically isolates one of the devices from the bus means upon occurrence of a fault condition.
In accordance with another aspect, the present invention provides a distributed vehicle safety system that includes a plurality of devices. Each of the devices performs a function associated with safety at a vehicle. The system includes a plurality of control means, each for controlling a respective one of the devices. Bus means conveys communication regarding the devices to the control means. The system includes means for electronically isolating one of the control means from the bus means upon occurrence of a fault condition.
In accordance with another aspect, the present invention provides a distributed vehicle safety system that includes a plurality of control/device arrangements. Each of the control/device arrangements accomplishes a function associated with safety at a vehicle. Bus means conveys communication to the control/device arrangements. A plurality of bus connector means connect the plurality of control/device arrangements to the bus means. Each bus connector means includes switch means for enabling communication between a respective control/device arrangement and the bus means and for disabling communication between the respective control/device arrangement and the bus means in response to a fault condition.